CN106873197A - A kind of glass structure of adjusting luminance and its negative dielectric anisotropic dye liquid crystal for using - Google Patents

Abstract

The invention provides a dimming glass structure and the negative dielectric anisotropy dye liquid crystal used therein. The dimming glass structure includes a building glass substrate and a liquid crystal cell. The building glass substrate on both sides forms a liquid crystal cell cavity. The liquid crystal cell is located in the liquid crystal cell cavity. The liquid crystal cell includes three layers of electronic glass, frame glue, and electrode leads , a controller, a battery board, and a photosensitive diode, the three layers of electronic glass and the frame glue form two adjacent liquid crystal cavities, the liquid crystal cavities are filled with negative dielectric anisotropy dye liquid crystals, and the two liquid crystal cavities The body is kept vertical in the direction of the light absorption axis, one end of the electrode lead is connected to the electronic glass, the other end is connected to the controller, and the battery board and the photodiode are connected to the controller. The cost is saved, and the compactness and reliability of the structure are also increased. At the same time, the direction of the dye light absorption axis of the two liquid crystal cells must be kept vertical to absorb visible light to the greatest extent.

Description

A dimming glass structure and the negative dielectric anisotropy dye liquid crystal used therein

technical field

The invention relates to the technical field of liquid crystal display, in particular to a light-adjustable glass structure and a negative dielectric anisotropy dye liquid crystal used therein.

Background technique

Liquid crystal display (LCD), as an important application of liquid crystal, a special material, has been widely concerned by people since the discovery of liquid crystal properties. In recent decades, especially with the rapid development of information technology and people's continuous pursuit of information display methods in the past ten years, liquid crystal display has achieved the most rapid development. Today, liquid crystal displays are being displayed in front of people in a variety of forms, and many of its products are becoming fashionable pursuits and popular commodities in shopping malls due to their excellent characteristics.

Liquid crystal display has experienced a long development path with the discovery of liquid crystal. In 1888, the Austrian botanist Friedrich Reinitzer discovered the first liquid crystal material, cholesterol benzoate (cholesteryl benzoate). In 1917, Manguin invented the rubbing orientation method to make monodomain liquid crystals and study optical anisotropy. In 1909, E.Bose established the theory of Swarm, which was supported by the experiments of L.S.Ormstein and F.Zernike et al. (1918), and was later discussed as statistical fluctuation by De Gennes. G.W.Oseen and H.Zocher founded the continuum theory in 1933, and it was perfected by F.C.Frank (1958). M.Born (1916) and K.Lichtennecker (1926) discovered and studied the dielectric anisotropy of liquid crystals. In 1932, W.Kast divided the nematic phase into two categories, positive and negative. In 1927, V.Freedericksz and V.Zolinao discovered that the nematic liquid crystal was deformed and had a voltage threshold (Freederichsz transition) under the action of an electric field (or magnetic field). This finding provides a basis for the production of liquid crystal displays.

In 1968, R.Williams of RCA Company in the United States discovered that the nematic liquid crystal forms stripe domains under the action of an electric field, and has light scattering phenomenon. G.H.Heilmeir then developed it into a dynamic scattering display mode and made it the world's first liquid crystal display (LCD). In 1968, Heilmeir and others in the United States also proposed the guest-host effect (GH) mode (dye liquid crystal). In 1969, Xerox proposed the Ch-N phase change storage mode. In 1971, M.F.Schiekel proposed the electrically controlled birefringence (ECB) mode, and T.L.Fergason et al. proposed the twisted nematic (Twisted Nematic: TN) mode. In 1980, N.Clark et al. proposed the ferroelectric liquid crystal mode (FLC). From 1983 to 1985, T .Scheffer et al. successively proposed the super twisted nematic (Super TwisredNematic: STN) mode and the active matrix (Active matrix: AM) mode proposed by P.Brody in 1972 was re-adopted. In 1986, Nagata proposed to use a double-layer box (DSTN) to realize black and white display technology; later, stretched polymer film was used to realize black and white display technology (FSTN). After 1996, reflective TN (RTN) and reflective STN (RSTN) modes using a single polarizer were proposed.

A dye is a substance that absorbs light of a specific wavelength, thereby causing the light reflected from it or transmitted through it to be colored. Certain dye molecules absorb light of a specific wavelength better if the light is polarized along one axis of the molecule. Such dyes are called dichroic dyes. After adding a dichroic dye into the liquid crystal, a mixed liquid crystal material for GH type liquid crystal display is formed. Due to the structural characteristics of liquid crystal molecules, the absorption of light along the molecular axis and the direction perpendicular to the molecular axis is different. The dye molecules dissolved in the liquid crystal show different colors under the action of an electric field, depending on the orientation of the molecules.

According to the similarities and differences of the control methods and principles, the switchable glass can be switched between the transparent and opaque states of the glass through various methods such as electric control, temperature control, light control, and voltage control. Among them, the dimming glass produced by temperature control, light control and voltage control technology is greatly affected by the environment, and it is not a self-controlled dimming glass in a complete sense.

The well-known suspendable particle-based switchable glass invented by Koreans is a switchable glass made by electrochromic technology. This kind of glass is between the two layers of glass of the dimming glass to adjust the transmission and scattering of light by controlling the number of suspended particles. The disadvantage of the dimming glass is that the cost is very high, and in order to prevent the leakage of particles, it is difficult The requirements of the use environment are very high. In addition to using electrochromic technology to make dimming glass, dimming can also be achieved through mechanical methods (for example, Chinese utility model patent ZL200320116206.8). This mechanical method is mainly to place two reels at both ends of the hollow laminated glass, and the reels are wrapped with a variety of colored films to achieve it. When it is necessary to shading, rotate a film of one color to shading, and when it is necessary to transmit light. , You can use the motor that controls the reel to collect the light-shielding color film. The biggest disadvantage of this mechanical method is that it needs manual operation, the structure is heavy, and the reliability is poor and the service life is short.

In addition, a known electro-adjustable glass is realized by polymer dispersed liquid crystal (PDLC) technology. The technology was invented in 1984 by a group led by Dr. Joseph W Doane of the University of Kent, US Patent US4688900. This technology uses water-insoluble polymer monomers, such as epoxy resins, and a curing agent to mix with liquid crystals to form a clear solution. When solidification occurs, due to the decrease in solubility, liquid crystal particles will automatically precipitate out and be suspended in the polymer phase. The process includes (1) preparing a solution of liquid crystal, epoxy resin and curing agent, (2) compounding the solution between two conductive films before curing, and (3) heating and curing the compounded film. The PDLC process can only produce positive-type products. Positive PDLC products are milky white when not electrified, and become transparent when electrified.

PDLC technology has a good switching state photoelectric effect, but requires continuous power supply to maintain a transparent state. In addition, due to the defects of the technology itself, there is an obvious viewing angle problem, that is, although it becomes transparent after being powered on, it still shows a certain degree of fog when viewed from the side viewing direction.

Contents of the invention

The invention provides a dimming glass structure and the negative dielectric anisotropy dye liquid crystal used therein, aiming to provide a hollow or vacuum glass, which can control the transparency of the glass to light through voltage, and realize the adjustment of indoor light , and at the same time play an energy-saving effect.

The invention provides a dimming glass structure comprising a building glass substrate and a liquid crystal cell. The building glass substrate on both sides constitutes a liquid crystal cell cavity. The liquid crystal cell is located in the liquid crystal cell cavity. The liquid crystal cell includes three layers of electronic glass, a frame Glue, electrode leads, controller, battery board, photodiode, the three layers of electronic glass and frame glue form two adjacent liquid crystal cavities, the liquid crystal cavities are filled with negative dielectric anisotropy dye liquid crystals, the The two liquid crystal cavities are kept vertical in the direction of the light absorption axis, one end of the electrode leads is connected to the electronic glass, the other end is connected to the controller, and the battery board and the photodiode are connected to the controller.

The invention provides a negative dielectric anisotropy dye liquid crystal for dimming glass, which mainly consists of a nematic liquid crystal component A containing negative dielectric anisotropy and one or more dichroic dye components B Composition, described component A comprises the compound of structural formula I, II, III, IV, V class, and all kinds of compound structural formulas are as follows:

Wherein, R1, R2, R3, R4, R5, R6 are independently alkyl or alkoxy groups with 2 to 9 carbon atoms;

m is 0 or 1, n is 0 or 1;

independently

independently

independently

independently

independently

independently

The present invention also provides a switchable glass structure, including electronic glass, electrode leads, a controller, a battery board, and a photosensitive diode. The electronic glass includes an electronic glass base, an ITO wire layer, a PI alignment layer, and a frame glue. The electronic glass base is connected to the ITO wire layer, the ITO wire layer is connected to the PI guide layer, the PI guide layer and the frame glue form a liquid crystal cavity, and the liquid crystal cavity is filled with the liquid crystal according to any one of claims 1 to 7. One end of the electrode leads is connected to the ITO wire layer, the other end is connected to the controller, and the battery board and photodiode are connected to the controller.

The beneficial effects of the present invention are: the present invention uses three pieces of glass to attach or arrange two independent liquid crystal cells together, which saves cost and increases the compactness and reliability of the structure. Orientation remains vertical for maximum absorption of visible light. By developing a dye liquid crystal with excellent negative dielectric anisotropy, the negative liquid crystal is used to realize the reverse display mode of the dimming glass, that is, the liquid crystal is arranged in parallel when the power is turned on, and absorbs light; when the power is turned off, the liquid crystal is arranged vertically and does not absorb light. Light, light passes through normally. Compared with the positive display mode, it has the characteristics of more energy saving and power saving, and the life extension due to the short working time.

Description of drawings

Fig. 1 is a structural schematic diagram of a switchable glass using a negative dielectric anisotropy dye liquid crystal according to the present invention;

Fig. 2 is a working principle diagram of the rearview mirror of the present invention under the condition of no power supply;

Fig. 3 is a working principle diagram of the rearview mirror of the present invention under the condition of power on.

detailed description

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments.

The present invention provides a dimming glass structure comprising a building glass substrate 6 and a liquid crystal cell 1. The building glass substrate 6 on both sides forms a liquid crystal cell cavity. The liquid crystal cell 1 is located in the cavity of the liquid crystal cell. The liquid crystal cell 1 includes three layers of electronic glass 2, a frame Glue 3, electrode leads 41, controller 42, battery board 43, photodiode 44, three layers of electronic glass 2 and frame glue 3 form two adjacent liquid crystal cavities, which are filled with negative dielectric anisotropy dye liquid crystals 5. The two liquid crystal cavities are kept vertical in the direction of the light absorption axis. One end of the electrode lead 41 is connected to the electronic glass 2 , and the other end is connected to the controller 42 . The battery board 43 and photodiode 44 are connected to the controller 42 .

Among them, the electronic glass 2 includes an electronic glass base 21, an ITO wire layer 22, a PI alignment layer 23, and a plurality of Spacer pads 24. The electronic glass base 21 is connected to the ITO wire layer 22, and the ITO wire layer 22 is connected to the PI guide layer. 23 connection, the PI guide layer 23 and the frame glue 3 form a liquid crystal cavity, a plurality of Spacer pads 24 are connected in the liquid crystal cavity at intervals, and the ITO wire layer 22 is connected to the electrode leads 41 .

Among them, the dimming glass structure also includes padding 8 provided with water-absorbing molecular sieves, and sealant 7. The sealant 7 is respectively connected to the upper and lower sides of the building glass substrate 6, and forms a sealed liquid crystal cell cavity with the building glass substrate 6. Body, the space between the liquid crystal cell 1 and the architectural glass substrate 6 is provided with a spacer 8 .

The invention provides a negative dielectric anisotropy dye liquid crystal for dimming glass, which mainly consists of a nematic liquid crystal component A containing negative dielectric anisotropy and one or more dichroic dye components B Composition, described component A comprises the compound of structural formula I, II, III, IV, V class, and all kinds of compound structural formulas are as follows:

Wherein, R1, R2, R3, R4, R5, R6 are independently alkyl or alkoxy groups with 2 to 9 carbon atoms;

m is 0 or 1, n is 0 or 1;

independently

independently

independently

independently

independently

independently

Wherein component B is one or more dichroic dyes of B-1 to B-22:

Wherein, component A is composed of compounds of various structural formulas in mass ratio, and its proportioning ratio is as follows: 30-70% of the compound of structural formula I, 5-30% of the compound of structural formula II, 25-50% of the compound of structural formula III, 0-10% of the compound of structural formula IV, 0-10% of the compound of structural formula V.

More preferred component A is composed of compounds of various structural formulas in mass ratio, and its proportioning is as follows: 40-50% of the compound of structural formula I, 10-20% of the compound of structural formula II, 30-40% of the compound of structural formula III, and 1-10% of the compound of structural formula IV , 1-10% of the compound of structural formula V.

In component A, the compound of structural formula I is one or more compounds of structural formula I-1 to I-16:

The compound of structural formula II is one or more compounds in structural formula II-1～II-10:

The compound of structural formula III is one or more compounds in structural formula III-1～III-15:

Embodiment one:

Ingredient A of the present invention is preferably the following components, and mixed in a certain proportion:

components weight percentage (%) I-1 15 I-2 15 I-5 10 I-7 7 I-9 8 II-5 7 II-9 8 III-1 25 III-6 4 III-11 4 IV 1 V 1

The performance parameters of the negative dielectric anisotropy nematic liquid crystal A1 obtained in this proportion are as follows:

performance parameter parameter value Cp 100°C Δε -3.6 Δn(25℃, 589nm) 0.100 Vth(V) 2.0

Embodiment two:

The negative liquid crystal containing dichroic dye of the present invention preferably has the following components, and is mixed in a certain proportion:

components weight percentage (%) A 98.8 B-20 0.3 B-21 0.6 B-22 0.3

The performance parameters of the negative dielectric anisotropy dye liquid crystal obtained in this proportion are as follows:

performance parameter parameter value color black responding speed <30ms

The reason why the dye liquid crystal with negative dielectric anisotropy is used is that when there is no voltage driving, the negative liquid crystal is vertically oriented, and the dichroic dye is also vertically oriented. At this time, the direction of the dye absorption axis is perpendicular to the light vibration direction, No light absorption, so that the bright state transmittance of the dimming glass reaches the highest; and when a driving voltage is applied to the negative liquid crystal molecules, the liquid crystal molecules are oriented in parallel under the action of the electric field, and the dichroic dyes are also oriented in parallel, and the dyes absorb light The axial direction is parallel to the light vibration direction, thereby absorbing light and making the dark state transmittance the lowest.

Prepare a three-sided double-layer liquid crystal cell with a vertical alignment layer, as shown in Figure 1, inject the dye liquid crystal prepared in Example 2 above into the liquid crystal cell, attach the liquid crystal cell to the inside of the building glass and make a hollow cell as shown in Figure 1 The structure of the glass is driven by a 5V, 70Hz square wave. The measured dark state transmittance is <25%, and the bright state transmittance is >75%, which fully meets the national building curtain wall standard.

The main feature of this structure is to manufacture two layers of liquid crystal cells on both sides of the same optical glass. The traditional preparation method is to use two layers of glass to prepare an independent liquid crystal cell, and then attach or list the two independent liquid crystal cells together. Four panes are required. This method only needs three pieces of glass, which not only saves costs, but also increases the compactness and reliability of the structure. The surface liquid crystal cell manufactured by this method needs to be filled with dye liquid crystals with negative dielectric anisotropy, and two liquid crystal cell dye liquid crystals are required at the same time. The direction of the absorption axis is kept vertical to maximize the absorption of visible light.

The liquid crystal cell of the present invention can be obtained by using the traditional liquid crystal display manufacturing process, especially the ODF mode is most suitable for liquid crystal perfusion, and the method of preparing one side first and then the other side is adopted.

The present invention is also equipped with an automatic control device for the liquid crystal box, which can use the solar panel to provide electric energy and store it, feel the intensity of sunlight through the photosensitive diode installed outside the window and adjust the voltage provided to the liquid crystal box through the circuit to realize the incident For the control of light intensity, of course, the present invention is also applicable to manual mode, which can be switched between manual and automatic as required.

Considering that the sunlight is relatively strong around noon, it is necessary to shield the light. Therefore, the present invention uses negative liquid crystals to realize the reverse display mode, that is, when the power is on, the liquid crystals are arranged in parallel and absorb light; when the power is off, the liquid crystals are arranged vertically and do not absorb light. Pass through normally. Compared with the positive display mode, it has the characteristics of more energy saving and power saving, and the life extension due to the short working time.

In order to realize automatic operation, the device is also equipped with a photosensitive circuit. As shown in Figure 3, when the photosensitive diode is exposed to strong light, the circuit is started immediately, and an electric field is applied to the liquid crystal. The liquid crystal is arranged in parallel with the electric field and drives the dyes to be arranged in parallel. The direction of the dye absorption axis is parallel to the direction of light vibration, thereby absorbing light. Reduce the light penetration rate, so as to prevent dizziness; as shown in Figure 2, when the strong light disappears, the photosensitive diode cannot feel the strong light, turn off the liquid crystal drive circuit, the liquid crystal restores the vertical alignment, and drives the dye molecules to align vertically , the direction of the light absorption axis of the dye is perpendicular to the light vibration direction, no light absorption, and the function of light transmission of the dimming glass is restored.

The above content is a further detailed description of the present invention in conjunction with specific preferred embodiments, and it cannot be assumed that the specific implementation of the present invention is limited to these descriptions. For those of ordinary skill in the technical field of the present invention, without departing from the concept of the present invention, some simple deduction or replacement can be made, which should be regarded as belonging to the protection scope of the present invention.

Claims (10)

1. a kind of glass structure of adjusting luminance, it is characterised in that including building glass substrate and liquid crystal cell, building glass base described in two sides Plate constitutes liquid crystal cell cavity, and the liquid crystal cell is located in liquid crystal cell cavity, and the liquid crystal cell includes three layers of electronic glass, frame Glue, contact conductor, controller, cell panel, light sensitive diode, three layers of electronic glass and frame adhesive constitute two adjacent liquid Filling negative dielectric anisotropic dye liquid crystal in brilliant cavity, the liquid crystal cavity, described two liquid crystal cavitys are in extinction direction of principal axis Keep vertical, described contact conductor one end connects electronic glass, its other end connection controller, the cell panel, photosensitive two pole Pipe is connected with controller.

2. glass structure of adjusting luminance according to claim 1, it is characterised in that the electronic glass include electronic glass pedestal, ITO conductor layers, PI both alignment layers, multiple Spacer distance pads, the electronic glass pedestal are connected with ITO conductor layers, and the ITO leads Line layer is connected with PI guide layers, and the PI guide layers constitute liquid crystal cavity, the multiple Spacer distance pads interval with frame adhesive It is connected in liquid crystal cavity, the ITO conductor layers are connected with contact conductor.

3. glass structure of adjusting luminance according to claim 1, it is characterised in that including being provided with bedding and padding of water molecules sieve, close Sealing, the fluid sealant is connected to the upper and lower both sides of building glass substrate, and the liquid sealed with building glass substrate composition Brilliant box cavity, the space being separated by between the liquid crystal cell and building glass substrate is provided with bedding and padding.

4. a kind of negative dielectric anisotropic dye liquid crystal for dimming glass, it is characterised in that main by each containing negative dielectric Anisotropy to lising liquid crystal composition A, being constituted containing one or more dichroic dye composition B, the composition A includes structure The compound of Formulas I, II, III, IV, V class, classes of compounds structure structural formula is as follows：

And/or

And/or

Wherein, R1, R2, R3, R4, R5, R6 are each independently 2 to 9 alkyl or alkoxy of carbon atom；

M is 0 or 1, n are 0 or 1；

Independently be

Independently be

Independently be

Independently be

Independently be

Independently be

5. the negative dielectric anisotropic dye liquid crystal of automobile rearview mirror is used for according to claim 4, it is characterised in that described Composition A is made up of in mass ratio each structural formula compound, and its proportioning is as follows：Compounds of structural formula I 30~70%, formula II Compound 5~30%, formula II I 25~50%, structural formula IV compounds 0~10%, structural formula V compounds 0~ 10%.

6. according to claim 4 be used for dimming glass negative dielectric anisotropic dye liquid crystal, it is characterised in that it is described into A is divided to be made up of in mass ratio each structural formula compound, its proportioning is as follows：Compounds of structural formula I 40~50%, formula II chemical combination Thing 10~20%, formula II I 30~40%, structural formula IV compounds 1~10%, structural formula V compounds 1~ 10%.

7. the negative dielectric anisotropic dye liquid crystal of automobile rearview mirror is used for according to claim 4, it is characterised in that described Composition B is one or more dichroic dye of B-1~B-22：

8. the negative dielectric anisotropic dye liquid crystal for dimming glass according to claim 4, it is characterised in that described The compound of structural formula I is one or more compound in structural formula I-1~I-16：

9. the negative dielectric anisotropic dye liquid crystal of dimming glass is used for according to claim 4, it is characterised in that the knot The compound of structure Formula II is one or more compound in formula II -1~II-10：

10. the negative dielectric anisotropic dye liquid crystal of dimming glass is used for according to claim 4, it is characterised in that described The compound of formula II I is one or more compound in formula II I-1~III-15：